Free MP3 Cutter - Free MP3 Cutter helps you slice off any unnecessary parts of an MP3 track you don't want.
Tune Sweeper - Show duplicates in your Music library. Automatically select which duplicates to keep and delete based on your preferences. Remove duplicates with one-click from your iTunes or Music app library.
MP3 Trimmer - With MP3 Trimmer - the most easy to use MP3 editor for Macintosh - you can edit MP3 files, join MP3...
iTunes Duplicate Song Manager - iTunes Duplicate Song Manager with Folder Watch removes iTunes duplicates in Windows and Mac OS X.
MP3 Splitter & Joiner - MP3 Splitter & Joiner is a MP3 audio editor.
SongGenie - SongGenie analyzes, identifies and repairs your mp3 tags and names.